Alex Jacobson (left), and Sam DeRose (bottom), both 17 years old, working on the Viper in San Rafael, Calif., on Wednesday, May 9, 2012. The Viper is a fighter jet flight simulator modeled after "Battlestar Galactica" built in the DeRose garage for the Maker Faire.

Photo: Liz Hafalia, The Chronicle

Alex Jacobson (left), and Sam DeRose (bottom), both 17 years old,...

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Clockwise from left--Sam DeRose, 17 years old, Tony DeRose (parent mentor), Sam Frank, 17 years old, and in simulator is Alex Jacobson (right), 17 years old looking at the monitors in a simulator they've made in San Rafael, Calif., on Wednesday, May 9, 2012.

Photo: Liz Hafalia, The Chronicle

Clockwise from left--Sam DeRose, 17 years old, Tony DeRose (parent...

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The flight simulator showing three screens from the cockpit in San Rafael, Calif., on Wednesday, May 9, 2012.

Photo: Liz Hafalia, The Chronicle

The flight simulator showing three screens from the cockpit in San...

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Mentors David Jacobson (middle) and Tony DeRose (right) helping Alex Jacobson (in simulator) work on the flight simulator in the DeRose garage in San Rafael, Calif., on Wednesday, May 9, 2012.

Photo: Liz Hafalia, The Chronicle

Mentors David Jacobson (middle) and Tony DeRose (right) helping...

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Mentor Tony DeRose (left) getting into the simulator as other oarents help students including Alex Jacobson (right) in San Rafael, Calif., on Wednesday, May 9, 2012.

Photo: Liz Hafalia, The Chronicle

Mentor Tony DeRose (left) getting into the simulator as other...

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David Jacobson (left) and Tony DeRose (right) mentor 13 year old Joe DeRose on his audio special effects for the Viper in front of the DeRose garage in San Rafael, Calif., looking through the backside of the simulaator on Wednesday, May 9, 2012. The Viper is a fighter jet flight simulator modeled after "Battlestar Galactica" and built in the DeRose garage for the Maker Faire.

It began with a ride on a fighter jet flight simulator at the Smithsonian's Air and Space Museum in Washington, D.C.

Joseph DeRose, 13, and his older brother Sam DeRose got off the ride and gushed about its coolness. Then they turned to each other and Sam, 17, said, "We should make something like this, only better."

The Smithsonian's flight simulator had a 30-degree range of pitch - the way its nose went up and down - but it could roll 360 degrees on its axis. They wondered: "Couldn't we do 360 on both pitch and roll?"

What they didn't know was that their idea would consume their every weekend for eight months and cost about $20,000. They didn't know that creating a motion-controlled flight simulator inspired by the television sci-fi series "Battlestar Galactica" would require finding a salvaged fuselage and doing hundreds of sketched prototypes and computer simulations.

They could not have known that it would require writing software, building a website, launching a fundraising campaign, and delving into detailed and vexing questions about horsepower and acceleration and the physics of rotational dynamics.

The one thing they may have envisioned: fighter pilot suits for everyone involved.

The ambitious project, code-named the Viper by a group of students from San Francisco and Marin, will make its official debut at the Maker Faire, the annual show-and-tell extravaganza this weekend that is part science fair and part county fair. Their goal is for visitors to be able to learn about the Viper - and fly in it.

Earlier this month, the young makers and their mentors and parents gathered in the DeRose garage-turned-workshop in San Rafael. The fuselage of a Piper PA-28 was set on a motion-control platform.

Tony DeRose, head of research at Pixar Animation Studios, smiled as the boys tested the simulator. The motors are capable of spinning at 17 rpm, which is about one revolution every three seconds, DeRose explained. Sound effects and visuals of takeoff, flying and landing were built in, along with layers of safety programs, including a roll bar and kill switches.

Sam DeRose built the first mechanical parts, and Alex added motors and wrote the first version of the software. Alex and Sam Frank worked on the cabin and instrument panel control inside the cockpit, tested the roll motor and did a rough cut balancing the center of gravity.

Cole and Novak spent nearly three months working with John on the computer-aided design models. The accuracy of the dimensions was critical when it came time to weld the parts. Sam DeRose did welding, and John did the laser cutting. They installed the monitors, laser-cut the acrylic panels for the operator console and labels, and figured out how to get power into the cabin.

"We moved up to this after doing projects for seven or eight years," Tony DeRose said. "It demonstrates the level kids can reach."

The group's first foray into the Maker Faire was in 2008, when Sam and Tony DeRose, interested in creating user interface devices, built a giant iPad-like touch display (this was before the iPad had been released). In 2009, they made a Potato Gatling Gun, an auto-firing, multibarrel version of the PVC potato cannon, capable of launching six potatoes 400 feet.

Next came Saphira, a 7-foot-tall, fire-breathing metal dragon inspired by the character Saphira in the book "Eragon." Last year's project was called Varia and was inspired by Joseph's favorite video game.

As the scope of the Viper project expanded, so did the cost. Joseph created the sound and visuals for their website and for Kickstarter, the online fundraising forum. They received $6,500 in corporate sponsorships and almost $12,000 through Kickstarter.

David Jacobson, watching his son, Alex, put on a helmet and climb into the simulator for a test flight, said, "The boys have done everything. This project has helped in so many ways. Developing problem-solving skills, collaborating as a team, learning leadership and figuring out how to architect and design something. It's an amazing hands-on lesson for a 16-year-old."

Smiling, Jacobson admitted to seeing other benefits: "He spends less time with his girlfriend, on Facebook and playing Xbox."

Just then, as the Viper began to pitch and roll - 360 degrees on both - someone joked: "Will this one shoot flames like Saphira?"

Alex said, "Only if we do something really wrong."

Tony DeRose, standing by the operating console, said, "As a researcher at Pixar, I invent things for a living. But there have been moments of discovery with the boys when some really elegant piece of the puzzle clicked. Those are the most satisfying moments of discovery I've ever had."

Sam DeRose, who is off to Harvey Mudd, a premier engineering college, in the fall, said, "This is the coolest thing ever. But what were we thinking?"